A Novel DC-Power Control Method for Cascaded H-Bridge Multilevel Inverter
Abstract– The cascaded H-bridge converter has been widely used in industry. The ability of dealing with unequal power generation among dc links is necessarily required in many applications, such as large-scale photovoltaic power plants and electric vehicles.A simplified modulation strategy is introduced to implement the proposed method, in which the duration times are modified directly by the correction value derived from the PCM method. The limitation and ranges of power generation ratio are analyzed in detail. DC power per phase can be controlled accurately by the proposed method in variable-frequency condition, even under larger power generation ratios. Results obtained from simulations and experiments are presented to verify the feasibilities and superiorities of the proposed method.